1. Field of the Invention
The invention refers to a method for producing a building board, wherein synthetic-resin layers are applied to the top side and/or the bottom side of a support board made of a wood material or a mixture of wood material and plastic, and the layered structure is compressed under the impact of pressure and temperature, as well as a building board produced according to this method.
2. Discussion of Background Information
A method of producing a building board is shown, e.g., from DE 102 52 861 A1. For example, flooring panels, which are widely used as a substitute for parquet flooring, are manufactured from building boards produced according to a method shown in DE 102 52 861 A1.
It is disadvantageous that, because of its structure and the gross density of the support board, a floor covering of such rigidity offers little comfort in terms of sound insulation and sound damping when someone walks on it. It is thus known to lay a floor covering, e.g., on a base of foam mats or elastic used floor coverings such as, e.g., short-pile carpets. But this is problematic with carpets or used floor coverings because of the installation height, and it is not free of expenditure because of the additional work of laying and fixing a foam mat.
Impact sound is produced through reflections of shock waves introduced into the floor when someone walks on it. In order to reduce these reflections, it is known, e.g., from DE 202 00 235 U1 to apply onto a building board a structured sound-insulating layer connected to the bottom side of the core. The structuring reduces the sound pressure values when someone walks on the floor, and the pertinent frequencies are shifted into a lower range.
The formation of the structure must either be taken into account when the thermoplastic material is brushed on or must be produced subsequently by heating or plasticizing areas of the thermoplastic material.
A counteracting impregnant for laminate floor panels is known from DE 10 2004 056 540 A1. The impregnant is composed of a resin-impregnated base paper onto one side of which a sound-insulating material layer is glued. Disadvantages are, on the one hand, the high costs of the paper ply forming the base of the counteracting impregnant and, on the other hand, that a counteracting impregnant of this type can be processed only in presses that are provided with a feeder of paper plies. Counteracting impregnants of this type cannot be used in integrated installations that print support boards directly and subsequently compress them.
The impact-sound insulation of a floor covering is certainly of great importance. For a person walking on a floor covering, however, the room sound is much more objectionable. The room sound is composed of the sound waves that are reflected directly or indirectly when someone walks on the floor.
From DE 100 34 407 C1 a laminate panel is known that is characterized by an insulating layer attached to the bottom side of the panel by means of strip gluing. The insulating layer is embodied shorter than the panel in the longitudinal and transverse directions. Since the insulating layer is embodied to be shorter than the panel, after the laying of the panels, air cushions arise both in the longitudinal and the transverse direction between each of the insulating layers of each panel. The cushions substantially increase the sound insulation, as the sound cannot be transferred beyond the panel joint since a compression of the insulating layer is largely avoided. This greatly reduces the room sound. Here, as well, the disadvantages are that a floor panel of this type cannot be produced in integrated installations, and the increased production expenditure through the additional work steps of applying the glue and the insulating layer.